Processing solutions have been applied to photographic materials using various methods. One method has been to use a high speed moving surface. It has been known to use high speed spinning drums to provide the high speed moving surface. In these arrangements, processing solution is retained in a tray through which the high speed moving surface passes. As the surface passes through the tray, it lifts processing solution out of the tray and carries it to a position where the solution is applied to the photographic material being processed.
In one arrangement where a high speed spinning drum is used, a mess blanket is used to hold the material against the drum surface. The drum is heated by hot water inside it. In another arrangement, a moving belt is used to transport the material across the surface of the spinning drum.
U.S. Pat. No. 3,192,846 discloses an arrangement in which photographic material is transported through processing apparatus on fluid layers formed one either side of the material. These fluid layers act as bearings for the material to prevent it becoming damaged during transportation. The fluid layers are applied by conduits positioned on either side of the material. The material is driven through the processing chamber by drive rollers positioned at either end. Another arrangement is also described in which rollers are used to guide material over a moving applicator belt as described above. Agitation is achieved when the linear speed of the applicator belt greatly exceeds the linear speed of the material being fed through the processing chamber.
In the applicator belt arrangements decribed above, large volumes of processing solution are required. This means that the processing solutions used need to be stable for relatively long periods of time.
In redox amplification processes where colour materials are developed to produce a silver image (which may contain only small amounts of silver) and then treated with a redox amplifying solution to form a dye image, the amplifying solution contains both an oxidising agent and a reducing agent and it is therefore inherently unstable. That is to say, unlike a conventional colour developer solution, amplifier solutions will deteriorate in less than an hour even if left in a sealed container. The best reproducibility for such a process has been obtained by using a "one shot" system, where the oxidant is added to the developer and the solution mixed and used immediately (or after a short built in delay) and then discarded. Such a "one shot" system cannot be used with the applicator belt arrangements described above as a relatively large volume of processing solution is required. Furthermore, the "one shot" system leads to the maximum solution usage possible with maximum effluent and maximum chemical costs. As a result the whole system is unattractive especially for a minilab environment where minimum effluent is required. It is believed that it is these shortcomings that have inhibited commercial use of this process.
It is therefore an object of the present invention to provide processing apparatus incorporating an applicator belt which uses small amounts of processing solution, and therefore overcomes the disadvantages mentioned above.